Make sure that in the communication program that you are using has the audio input set to realtek high definition audio and if you are using a laptop check if there is 1 or 2 audio jacks and if there are 2 or you are using a desktop make sure that you are using the "dongle" /splitter and plug the plug with the pink stripes to the pink audio jack or the one with a microphone symbol and the the other plug with green stripes to the green plug or the one with headphone/speaker symbol.You can use either the front panel or the or the motherboards own io. If you have a laptop with only one audio jack, make sure that you don't have the "dongle"/splitter attached and plug the audio jack in. If this doesn't work tell more about your system. Like is it a laptop and if it's not, then tell me are you using a soundcard or integrated audio and if you are using an external soundcard/DAC.